Synonyms

Benign smooth muscle tumour

Category

Soft tissue

Behaviour

Benign

Gender

Female

Tissue of Origin

Smooth muscle

Epidemiology

• Most common Benign soft tissue tumour
• Arise from smooth muscle of blood vessels or dermis
• Multiple lesions in some patients

Clinical Features

• Firm subcutaneous nodule
• Often painful (angioleiomyoma)
• Slow-growing

Location

• Skin and subcutaneous tissue
• Often on extremities
• Can arise from Vascular smooth muscle

Imaging

• Ultrasound: hypoechoic nodule
• MRI: well-defined mass

Pathology

• Mature smooth muscle cells arranged in fascicles
• No atypia or mitotic activity

Genetics

• Sporadic
• FH gene inactivation in some

Treatment

• Observation for asymptomatic lesions
• Excision if painful or enlarging

Prognosis

Excellent - no malignant potential

Key Points

• Benign smooth muscle tumour
• No Malignant transformation

Workup - Blood Tests

No blood tests required

Workup - Local Imaging

Ultrasound or MRI for characterisation

Workup - Biopsy

Rarely required

Workup - Staging

No staging required

Workup - Other

Observation standard for asymptomatic lesions